Hourly Weather | Today Friday, September 18, 2026
Stamford, Connecticut
12 PM
Cloudy Weather
79°
Feels Like 82°
20
Humidity: 55%
UV Index: 5
Wind: 9 mph
1 PM
Cloudy Weather
81°
Feels Like 84°
13
Humidity: 55%
UV Index: 5
Wind: 8 mph
2 PM
Cloudy Weather
81°
Feels Like 84°
0
Humidity: 52%
UV Index: 5
Wind: 8 mph
3 PM
Cloudy Weather
82°
Feels Like 84°
0
Humidity: 50%
UV Index: 4
Wind: 9 mph
4 PM
Cloudy Weather
81°
Feels Like 82°
0
Humidity: 51%
UV Index: 3
Wind: 9 mph
5 PM
Cloudy Weather
79°
Feels Like 79°
0
Humidity: 53%
UV Index: 2
Wind: 9 mph
6 PM
Cloudy Weather
79°
Feels Like 75°
0
Humidity: 55%
UV Index: 1
Wind: 8 mph
7 PM
Cloudy Night
75°
Feels Like 73°
0
Humidity: 59%
UV Index: 0
Wind: 7 mph
8 PM
Cloudy Night
72°
Feels Like 70°
0
Humidity: 64%
UV Index: 0
Wind: 7 mph
9 PM
Cloudy Night
70°
Feels Like 66°
0
Humidity: 67%
UV Index: 0
Wind: 7 mph
10 PM
Cloudy Night
68°
Feels Like 66°
0
Humidity: 66%
UV Index: 0
Wind: 7 mph
11 PM
Cloudy Night
66°
Feels Like 64°
0
Humidity: 65%
UV Index: 0
Wind: 8 mph

Hourly Air Quality Forecast - AQI (US EPA)

12 PM
60 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 16.54 µg/m³
  • PM10: 19.41 µg/m³
  • O3: 0.044 ppm
  • NO2: 7.7 ppb
  • SO2: 1.8 ppb
  • CO: 0.22 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

1 PM
70 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 19.17 µg/m³
  • PM10: 21.86 µg/m³
  • O3: 0.060 ppm
  • NO2: 5.5 ppb
  • SO2: 1.6 ppb
  • CO: 0.21 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

2 PM
113 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 22.41 µg/m³
  • PM10: 24.95 µg/m³
  • O3: 0.074 ppm
  • NO2: 3.7 ppb
  • SO2: 1.5 ppb
  • CO: 0.21 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

3 PM
137 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 23.48 µg/m³
  • PM10: 25.8 µg/m³
  • O3: 0.081 ppm
  • NO2: 2.8 ppb
  • SO2: 1.4 ppb
  • CO: 0.20 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

4 PM
142 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 22.89 µg/m³
  • PM10: 25.05 µg/m³
  • O3: 0.083 ppm
  • NO2: 2.8 ppb
  • SO2: 1.4 ppb
  • CO: 0.20 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

5 PM
135 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 21.27 µg/m³
  • PM10: 23.33 µg/m³
  • O3: 0.081 ppm
  • NO2: 3.5 ppb
  • SO2: 1.3 ppb
  • CO: 0.19 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

6 PM
118 AQI
Unhealthy air quality for sensitive groups Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 19.06 µg/m³
  • PM10: 21.08 µg/m³
  • O3: 0.075 ppm
  • NO2: 4.8 ppb
  • SO2: 1.3 ppb
  • CO: 0.19 ppm

Health Recommendations:

Members of sensitive groups may experience health effects. The general public is less likely to be affected.

7 PM
92 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 16.66 µg/m³
  • PM10: 18.75 µg/m³
  • O3: 0.068 ppm
  • NO2: 6 ppb
  • SO2: 1.2 ppb
  • CO: 0.19 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

8 PM
69 AQI
Moderate air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 14.55 µg/m³
  • PM10: 16.78 µg/m³
  • O3: 0.060 ppm
  • NO2: 6.3 ppb
  • SO2: 1.2 ppb
  • CO: 0.19 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

9 PM
51 AQI
Moderate air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 12.55 µg/m³
  • PM10: 14.94 µg/m³
  • O3: 0.053 ppm
  • NO2: 6.4 ppb
  • SO2: 1.2 ppb
  • CO: 0.19 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

10 PM
43 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 10.38 µg/m³
  • PM10: 12.89 µg/m³
  • O3: 0.046 ppm
  • NO2: 6.6 ppb
  • SO2: 1.1 ppb
  • CO: 0.18 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 PM
36 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.19 µg/m³
  • PM10: 10.65 µg/m³
  • O3: 0.039 ppm
  • NO2: 6.9 ppb
  • SO2: 1.2 ppb
  • CO: 0.18 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.